Apparatus for gaging engine-pistons



L. R. SPENCER.

APPARATUS FOR GAGING ENGINE PISTONS.

APPLICATION FILED OCT. 14,1919.

Patentd Apr..19, 1921.

-L. R. SPENCER.

APPARATUS FOR GAGING ENGINE PISTONS.

APPLICATION men-oer. 14, 1919.

1,375,237, Patented Apr. 19, 1921.

2 ISHEETSSHEET 2.

- journals.

LOUIS R. SPENCER, 0F HARTFORD, CONNECTICUT.

APPARATUS FORGAGING ENGINE-PISTONS.

Specification of Letters Patent. Patented Apr. 19, 1. }21.

7 Application filed October 14, 1919. Serial No. 330,533.

T 0 all whom it may concern: I Be it known that I, Louis R. SPENCER, citizen of the United States, residing at Hartford, in the county of I-Iartfordand State ofConnecticut, have invented a new and useful Improvement in Apparatus for Gaging Engine-Pistons, of which the following is a specification.

The pistons of internal combustion engines are fitted closely to the bores of the cylinders in order to insure efliciency, consequently it is necessary that the axes of the pistons coincide with the axes of the cylinders. Frequently when setting up engines and particularly after they have been taken vdown for cleaning or repairs, it is found that the pistons'do not aline perfectly with the cylinders, that is, the surfaces of the pistons are not parallel with the surfaces of the cylinders. This causes a binding of the pistons on one side at the'top and on the opposite side at the bottom, which condition may result from uneven "wear of the piston-rod hearings or from the springing of the piston-rods, and if not remedied produces excessive strains on the bearings, undue wear and scoring of the cylinder walls and piston'surfaces and makes the engine run hard and with greatly reduced efficiency.

The object of this invention is to provide .a simple apparatus by means of which the surface alinement of the piston seton the crankshaft ofan internal combustion enginemay be readily ascertained, so that if inaccurate the fault may be easily observed and quickly remedied by bending the piston-rods or scraping the bearings the nec essary amount.

Figure 1 of the accompanying drawings shows a front elevation of a form of apparatus which embodies the invention illustrating its use in gaging a piston from the crank shaft on which it is set. In this fern the gaging is accomplished from the shaft the same with thepiston omitted. Fig. 3 shows a front elevation of a modified form of the apparatus illustrating its use when gaging pistons from the upper machined surface of the crank case. Fig. l shows a side elevation of the modified form in use.

The apparatus which forms the subject of this invention has a bar 1 with a straight edge 2. Movable back and forth on this bar is a head 3 with a dependlng gage arm 4.

Fig. 2 shows a side elevation of The head has a straight edge 5 which is held closely against the straight edge 2 on the bar by means of: a spring 6 located in the top of the head and bearing on the top of the barn The arm which depends from the head has two straight edges 7 which when the'head is on the bar are at right angles to the straight edge 2.

Attached to the bar near each end is a leg 8. In the form first illustrated this leg near the bottom has a forwardly projecting bracket 9 andat the bottom has a forwardly extending. foot. 10. The foot has athreaded perforation turning in which is a thumb screw 11 with a block 12 swiveled on its up per end.

In using this form of the invention'the brackets 9 are'rested upon the upper side of the journals 13 of the crank shaft 14, and the blocks 12 are, by means of the thumb screws, set up against the under side of the crank shaft journals. When the apparatus is secured n this manner the straight edge on the bar is parallel with the axis of the shaft. The head is then moved along until one of the straight edges on the arm depend ing from the head-comes into contact with the side of the piston 15. If the piston is out of true, as shown bythe gage, the piston-rod 16 may be bent until the piston gages true, or the rod maybe disconnected from the'sha'ft and the bearings 17 scraped until the piston when remounted does gage true. f For gaging pistons already set in the crank ease, as illustrated in Figs. 3 and 4, the bar, head and arm may have the same construction as already described. For use under these circumstances'the legs 18 may be provided'with outwardly extending feet 19 through which are slots 20. The under faces of these slotted feet areparallel with and equal distances from the straight edge of the bar and they are placed upon the top machined surface 21 of the crank case 22 Over the crank case bolts 23, then nuts'24t are screwed upon the bolts to hold the structure rigid. If desired, cars 25 with several perforations 26 may be formed on the back of the bar for receiving the upper ends of the legs, and nuts 27 may be-screwed on the upper threaded ends of the legs to secure the parts together.

tobe set'over crank case bolts which are This permits the feet different distances apart.

When the apparatus is mounted in this manner the shaft is turned to elevate first one piston and then the other, each piston being gaged and set when it is up.

This apparatus can be quickly attached to engine shafts or to crank cases and the al'inement of pistons accurately insured so that they will fit into the cylinders without binding.

The invention claimed is: 1. An apparatus for gaging pistons comprising a bar with a straight edge, supporting legs depending from the bar, means prising a'bar'with a straight edge, supporting legs depending from the bar, means at the ends of the legs for fixing them -in position with the straight edge of the'bar at right angles to the surface to be 'gaged, a gaging arm with a straight edge extending at right angles to the straight edge on the bar, said arm being movable backa'nd forth toward and from said supporting legs'along the. entire length and off the ends of the 7 bar without removin the bar "from the supporting legs, and'a spring for retaining said arm with the straight edge onthe arm atalltimes at right "anglesto the straight edge on the ban? v 3. An apparatus for gaging pistons comprising a bar, supporting legs depending from the bar, clamping feet at "the lower ends of the legs, and a gaging arm movable back and forth along the bar;

"4;. An apparatus for gaging pistons comprising a bar with a straight edge, supporting legs adjustably fixed to the back of the bar, means at the ends of the legs for fixing them in position with the straight edge of the bar at right angles to the surface to be gaged, and a gaging arm with a straight edge extending at right angles to the straight edge on the .bar, said arm being movable transversely back and forth toward and from said supporting legs. along the entire length and off the ends of the bar without interference "by the supporting legs.

5. An apparatus for gaging pistons com prising a bar with a straight edge, supportinglegs depending "from the bar, means at the ends of "the legs for securing thernin position with the strai ht edge of the bar at right angles to the surface to be gaged,

'a head movable back and forth the entire length of the "bar, and a gaging arm with straight edges on opp'osite'sides extending at right angles to the straightedge on the bar, depending from the head.

.6. An apparatus for gagingv pistons coniprising a bar, supportln'g legs depending from the bar,'*brackets eXtending forward from the legs near their loweren'ds, per

forated feet extending forward from the legs at their lower'ends, thumb screws turning through said "feet, blocks sw ve'led on the upper ends o fsa'id fthumb -screws, and a gaging arm movable backand forth along the bar.

T. An apparatusf'orgaging'pistons comprising a bar, supporting legs, depending from the bar, clarnps the lower ends of. the legs for securing them in pos1ft1on,* a

head embracing and adapted tomove-along said bar, a spring carried by said head and engaging the bar-,aad a gaging arm depending from said head atright angles to 'the bar. M I

' V LOUIS R. SPENCER. 

